Sunderland boss Roy Keane is convinced former club Manchester United will retain their Barclays Premier League title after seeing his side demolished by Alex Ferguson's side yesterday.

United maintained the pressure on Arsenal with a comprehensive 4-0 victory at the Stadium of Light to leave Keane's Sunderland deep in relegation trouble.

Ferguson's men simply had too much for the top-flight novices and raced into a 3-0 lead before the break.

Louis Saha's 86th-minute penalty simply cemented a win which had long been in the bag to leave Keane in little doubt as to the season's outcome.

He said: "I have been asked this question for the last month or two and I have said before my money is still on United and today has not changed that, it has not wavered it one bit.

"Any team that wins the league, history will tell you - and the manager of United has got so much experience - that they will get stronger as the season goes on.

"We did not kid ourselves when we were beaten 1-0 down there. It's like ourselves, it takes eight, nine, 10 games to get into the swing of things, even more so for the big boys who might have brought in one or two big signings.

"United, as the manager has said, if they are there or thereabouts coming into the new year, they will have a hell of a chance and I would not disagree with that one bit."

United were on their way with just 20 minutes gone when Wayne Rooney ended his six-game wait for a goal with an unerring finish.

He then turned provider to allow Saha to double the lead on the half-hour, and Cristiano Ronaldo, who had earlier forced Craig Gordon into two important saves from free-kicks, finally beat him with a third in first-half injury time.

From then on, it was simply a matter of by how many United won, although they had to wait until the death for number four.

Ferguson was understandably delighted with his strikers in particular.

Asked about Saha's goal, he said: "It will do him a load of good, his confidence. We were having no problems at all - he and Rooney worked particularly well together and they were a real threat today."

Keane, who handed a debut to 17-year-old striker Martyn Waghorn, was defiant after a defeat which left his side just one place off bottom.

He said: "We are where we are. The best team will win the league and the three worst teams will go down - and I believe we are not one of the three worst teams in the Premier League.

"But it would be nice to back that up with some positive results and some wins.

"We are doing okay. We have got lots going for us in terms of the spirit of the players, the attitude of the players, and I am very lucky with the support and the staff I have got.

"But again, I keep saying, we do need a few more players of real quality."